Novi pristup priređivanju molekulski tiskanih polimera

U radu je opisana sinteza i polimerizacija akrilnih monomera koji imaju dicikloheksilureu (DCU) u bočnom lancu. Polimerizacijom akril-DCU s etilen-glikol dimetakrilatom (EDMA) do visoke konverzije, u butanonu s benzoil-peroksidom (Bz2O2), pri temperaturi od 70 °C sintetizirani su umreženi kopolimeri različitog sastava. Pri uvjetima kontrolirane termičke razgradnje u TG analizatoru, u temperaturnom području od 100 °C do 500 °C u struji dušika, kopolimeri se razgrađuju dvostupnjevitim mehanizmom. U prvom stupnju, od 180 °C do 250 °C, izdvaja se cikloheksilizocijanat. Ostatci nakon uklanjanja izocijanata termički su stabilni molekulski tiskani (nanoporozni) kopolimeri akril-cikloheksilamida (A-CHA) s EDMA, koji se razgrađuju u jednom stupnju pri temperaturi od 300 °C do 450 °C. Radi usporedbe svojstava molekulski tiskanih, nanoporoznih kopolimera poli(A-CHA-ko-EDMA) s odgovarajućim neporoznim kopolimerima, sintetizirani su neporozni kopolimeri A-CHA s EDMA pri navedenim uvjetima.
This paper describes the synthesis and polymerization of acrylic monomers which contain dicyclohexylurea (DCU) as a pendant group. Crosslinked copolymers of these monomers with ethylene glycol dimethacrylate (EDMA) were prepared under the standard free radical initiated polymerization with dibenzoyl-peroxide (Bz2O2) as initiator, in butanone at 70 °C, up to high conversion. It was found that copolymers, regardless of the ratio of comonomers in the feed, thermally decompose by the two-step mechanism under the separation of almost quantitative yield of cyclohexylisocyanate, in the temperature range from 180 °C to 250 °C. The residues left by the removal of isocyanate were thermally stable crosslinked molecularly imprinted copolymers of acryl-cyclohexylamide (A-CHA) with EDMA, which decompose by a one-step mechanism between 300 °C and 450 °C. In order to compare the properties of nanoporous crosslinked copolymers of A-CHA with EDMA with those of nonporous poly(A-CHA-co-EDMA) of the same molar composition, nonporous copolymers were prepared by the polymerization of A-CHA with EDMA under the conditions described above.